In Patent Document 1, there is described a technique of a temperature compensating device of a color liquid crystal display elements. An object of this technique is to make it possible to appropriately modify optimal output voltage data for temperature according to a variation or a temporal change for each of a plurality of color liquid crystal display elements. FIG. 14 is a block diagram showing a configuration of this device. As shown in FIG. 14, this device includes a temperature sensing circuit 211, a data table 212 in which digital optimal output voltage data for temperature are stored, and from which optimal output voltage data corresponding to temperature data from the temperature sensing circuit 211 are read out, voltage correction means 217 for correcting the optimal output voltage data read out from the data table 212, a D/A conversion circuit 213 which converts the optimal output voltage data from digital to analog, to transmit the data to a drive circuit of the liquid crystal display element, an operating unit 216 that provides correction data to the voltage correction means 217, and control means 214 for modifying the optimal output voltage data for temperature in the data table 212 based on correction data from the operating unit 216 and temperature data from the temperature sensing circuit 211.
Further, in Patent Document 2, there is described a technique of a liquid crystal panel driving device which drives a liquid crystal panel at a high speed by overdrive. FIG. 15 is a block diagram showing a configuration of this liquid crystal panel driving device. This liquid crystal panel driving device is a device which performs overdrive by use of a frame memory 231 and a lookup table 232, and includes plural types of lookup tables 232 corresponding to different temperature ranges. This device activates a selection circuit 233 so as to switch among the lookup tables 232 to use those based on temperature information of an LCD module 234 obtained from a temperature sensor 235.
Further, in Patent Document 3, there is described a technique of a semi-transmissive liquid crystal display device. FIG. 16 is a block diagram showing a configuration of this liquid crystal display device. This liquid crystal display device includes a correction circuit 241. The correction circuit 241 has a lookup table selection unit 242, a plurality of lookup tables for transmissive mode 243, a plurality of lookup tables for reflective mode 253, a frame memory 244, a mode determination unit 245, a switch 246, and a switch control unit 256. The lookup tables for transmissive mode 243 and the lookup tables for reflective mode 253 store correction values (correction gradations) in which temporal changes in signal are emphasized so as to correspond to combinations of current gradations and target gradations. In addition, FIG. 17 is a table showing a configuration example of this lookup table for reflective mode 253.
The switch control unit 256 stores a threshold value Y for an ambient temperature, and outputs a low-level switch control signal SC when a mode selection signal MD output from the mode determination unit 245 is at a low level or an ambient temperature T0 output via an A/D converter 247 from the temperature sensor 248 is lower than or equal to the threshold value Y, and outputs a high-level switch control signal SC in the other case. A correction gradation output from the lookup table for transmissive mode 243 or the lookup table for reflective mode 253 which is selected by the lookup table selection unit 242, an input video signal V1, and the switch control signal SC are input to the switch 246. The switch 246 outputs the correction gradation when the switch control signal SC is at a low level, and outputs the input video signal V1 when the switch control signal SC is at a high level, as a correction video signal V2.